> His example of how PSK63 would be great for contests because you could say
> "hi there and goodbye" in addition to the exchange really is ridiculous.
If
> you give AA5AU twice the sending speed he is going to use that time to
work
> more stations -- not to discuss his life.
Yes, I doubt that Don would want to use the PSK63 "advantage" of sending his
thumbnail image during a contest.
> The supposed power advantage to PSK is overstated. They ignore issues of
IF
> bandwidth, receiver dynamic range, phase distortion on bad paths, and
> frequency stability. MMTTY will copy into the noise. Sure PSK has a few
db
> of advantage but the QRP thing is all hype. In addition, of course, if we
> go to PSK63, any serious contestant is going to run as much power as his
> power class allows. So the argument that you can only run 5 watts will go
> to pieces.
Witness the winner of the first ARRL Roundup PSK31 plaque - won with 1000
watts.
> How a bunch of canned messages saying that you're
> running a Mark IV with Rig Blaster and an old IBM laptop is interesting is
> beyond me!
There is a lot of philosophy in Mike's remark above. If you don't see it,
you're probably standing too close to the mirror.
> Lastly, in a
> contest situation the theory of running 2.1khz bandwidth and sorting
things
> out in the audio card and clicking on multilple "tracks" from a waterfall
is
> not going to work. The strongest signal in the bandwidth is going to
> capture the AGC and the weak ones just fade away. The solution, of
course,
> is to defeat the AGC by turning down the RF gain -- but the real
solution --
> and one that will let you use this wonderful bandwidth advantage -- is to
> crank your IF selectivity down to 50hz. Imagine 20 of the biggest RTTY
signals all crammed into one 2.1 > hz passband. What a mess.
Check out how this works visually at http://www.qsl.net/wa9als/passband.htm
When's the next RTTY contest?? The fact that PSK is bringing more guys into
RTTY contesting is a good sign! 73 - John, WA9ALS
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